WO1996014281A1 - Process for the removal of color forming material from 1,4 butanediol and its application to the preparation of ptmeg - Google Patents
Process for the removal of color forming material from 1,4 butanediol and its application to the preparation of ptmeg Download PDFInfo
- Publication number
- WO1996014281A1 WO1996014281A1 PCT/US1995/014849 US9514849W WO9614281A1 WO 1996014281 A1 WO1996014281 A1 WO 1996014281A1 US 9514849 W US9514849 W US 9514849W WO 9614281 A1 WO9614281 A1 WO 9614281A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- butanediol
- methyl
- alkyl
- impurities
- dioxolane
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
- C08G65/02—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring
- C08G65/04—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring from cyclic ethers only
- C08G65/06—Cyclic ethers having no atoms other than carbon and hydrogen outside the ring
- C08G65/16—Cyclic ethers having four or more ring atoms
- C08G65/20—Tetrahydrofuran
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/80—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by distillation
Definitions
- This invention relates to a method of removing precursors to undesirable color forming impurities prior to production of polytertramethylene ether glycol (PTMEG) and related copolymers. More specifically, but not by way of limitation, this invention relates to an improved method of removing precursors to color forming acetals in 1 ,4-butanediol or mixtures of 1 ,4-butanediol with lower alkyl-substituted 1,4-butanediols by distillation prior to the ring closing cyclization to corresponding tetrahydrofiiran (THF) and 3-alkyl tetrahvdrofuran (3-alkyl THF) and subsequent polymerization to produce PTMEG.
- THF tetrahydrofiiran
- 3-alkyl tetrahvdrofuran 3-alkyl THF
- the improved method of producing polytetramethylene ether glycol polymer or copolymer of improved color involves the steps of:
- step (b) subjecting the topped 1.4-butanediol stream produced in step (a) to catalytic cyclization thus producing tetrahvdrofuran optionally containing one or more 3-alkyl-substituted tetrahydrofiiran, wherein said cyclic product stream is characterized as substantially free of 1,3-dioxolane and 4- alkyl- 1,3-dioxolane impurities; and
- step (c) polymerizing the tetrahydrofiiran optionally containing one or more 3- alkyl-substituted tetrahydrofiiran produced in step (b) thus producing polytetramethylene ether glycol polymer of improved color index.
- the starting 1,4-butanediol is itself a commercial distillate of relatively high total diol content (typically 99.9 wt% diol) which may have from trace amounts up to as much as about 16 wt% of 2-methyl- 1,4-butanediol derived from the presence of formaldehyde (either produced inherently in situ or intentionally added) during the hydrogenation of butynediol used to manufacture the 1,4-butanediol (see U.S. Pat. Nos. 4,590,312 and 4,590,285).
- formaldehyde either produced inherently in situ or intentionally added
- the 1 ,4-butanediol under these conditions may, itself, be the formaldehyde source, an explanation that is at least consistent with long felt need for improvement and the admission in the previously mentioned prior art patent 5.1 12,943 that technical grade THF contains small amounts of impurities in a concentration of from 10 to 500 ppm. the chemical nature of which is not known in any great detail and which cause discoloration and modify reactivity in the preparation of polyesters or polyurethanes.
- the intentional spiking of the 1.4-butanediol with an additional ethylene glycol and 1,2-propylene glycol with and without additional spiking of formaldehyde and the resulting detection of significant increases in 1 ,3-dioxolane and 4-methyl- 1 ,3-dioxolane in the topped overhead tends to support and confirm these observations and their interpreted significance (i.e., the proposed mechanistic explanation).
- the fact that the additional spiking was at relative high concentrations further verifies that method according to the instant invention is operative at least over the concentration range of interest associated with the production commercial grade THF (i.e., essentially 99.9 wt % THF).
- the distillation or topping of the 1,4-butanediol liquid phase (with or without the presence of one or more 2-alkyl-l,4-butanediols) and the removal of the lower boiling glycols can be performed by any of the distillation methods and equipment as generally known and practiced in the art.
- the topping of the 1 ,4-butanediol is performed as a steady state distillation with the overhead containing the undesirable lower alkyl glycols (i.e., ethylene and propylene glycols) and other low boiling components.
- the purified 1,4-butanediol stream is removed lower on the distillation column as either a liquid or vapor as generally known in the art. It should be readily appreciated that various other configurations and equipment can be employed to accomplish the topping step and as such should be considered equivalent for purposes of this invention to that specifically illustrated herein by way of example.
- the conversion of the 1,4-butanediol and 2-alkyl- 1 ,4-butanediol to tetrahydrofiiran and 3-alkyl-tetrahydrofuran, respectively, can be accomplished by any of the catalytic dehydration/cyclization reactions as generally known in the art.
- the cyclization reaction involves the use of an acidic catalyst such as a sulfonic acid, Lewis acid, non-oxidizing mineral acid, acidic cation exchange resins or the like.
- the cyclization reaction can be accomplished by using sulfuric acid as described in U.S. Pat. No. 3.726.405.
- the THF and 3-alkyl THF produced by catalytic cyclization is dried and further refined by adjusting the pl l and subjecting the cyclic ethers to a multi-stage distillation such as described in U.S. Pat. No. 4,093,633 or the like.
- the polymerization of the tetrahvdrofuran, with or without one or more 3-alkyl-substituted THFs is accomplished by cationic polymerization.
- any of the commercially acceptable acidic catalytic methods, with or without various molecular weight control agents can be utilized: including by way of example but not by way of limitation; fluorosulfonic acid; ion exchange resin bearing the -SO3H groups; carboxylic anhydrides with strong acid such as the acylium ion precursor acetic anhydride and a polymeric catalyst containing the -SO3H groups and the like.
- fluorosulfonic acid or a polymeric resin containing -SO3H groups such as Nafion® are used as the catalyst.
- the improved method for reducing discoloration of PTMEG according to the instant invention can also be advantageously used in combination with various other techniques for alleviating discoloration as generally known in the art.
- the instant process is viewed as controlling color by removal of low boiling precursors to acetal formation, previous known techniques associated with catalytic hydrogenation of other color forming impurities should also be employed when it is suspected that these other impurities are present.
- 4,257,961 describes a method of reducing the concentration of methacrolein, dihydrofuran, propionaldehyde and butyraldehyde impurities present in THF made from acetylene and formaldehyde.
- the hydrogenation of the THF distillate is employed in combination with the instant process as will be further illustrated in the Examples herein.
- V Total of L + D (grams/minute)
- the topped l,4-butanediol/2-methyl- 1.4-butanediol samples were then converted to tetrahydrofuran/3-methyltetrahydrofuran in a continuous cyclization unit held at 125 °C with about 4.0 wt°/o sulfuric acid catalyst and 7.0 grams Hastello ⁇ -C turnings.
- the unit consisted of a one liter round-bottom flask with a 5 plate Oldershaw column on top. a water-cooled condenser, and a w ater- cooled graduated distilling receiver which could be drained into product collection containers or small bottles via a 3-way valve.
- Topped l .4-butanediol/2-methyl- l ,4-butanediol was pumped out of the feed container into the reaction pot. A portion of the cylized product was pumped back to the top of the Oldershaw column as reflux. Reflux ratio was controlled at about 0.3 by adjusting the reflux pump rate. The entire system was kept under a nitrogen atmosphere. Topped 1.4- butanediol/2-methyl- 1 ,4-butanediol from run BDOTl was fed to the cyclization unit for 34 hours, followed by topped l,4-butanediol/2-methyl- 1,4-butanediol from run BDOT2 for 29 hours.
- This partially dried material was then passed through a 2 inch diameter glass column packed with 4A molecular sieves to reduce its water content to about 0.03 wt%.
- the dried product was then hydrogenated in a one-half inch diameter trickle bed reactor using Raney nickel 2800 as the catalyst.
- the reactor was operated at 90 °C and 130-140 psi hydrogen pressure.
- the hold-up time was 7-10 minutes based on liquid flow rate.
- a portion of the refined tetrahvdrofuran '3-methyltetrahydrofuran product (characterized as having 10 ppm of 1.3-dioxolane and no measurable 4-methyl- 1,3-dioxolane) was diluted to about 30 wi% 3-methyltetrahydrofuran with tetrahydrofiiran, and this solution was polymerized with flurosulfonic acid, FS0 3 H. catalyst for four hours at 35 °C (about 200 grams THF/3-methyl THF to 22.9 grams FSO3H). After quenching the catalyst with water, unreacted material was distilled off, the copolymer washed several times with water, and then lime was added for neutralization.
- the continuous cyclization unit was held at ⁇ 125 °C with about 4.0 wt% sulfuric acid catalyst and 7.0 g Hastelloy-C turnings.
- the unit consisted of a one liter round-bottom flask with a 5 plate Oldershaw column on top, a water- cooled condenser, and a water-cooled graduated distilling receiver which could be drained into product collection containers or small sample bottles via a 3-way valve.
- the a desalted, commercial grade mixture of 1 ,4-butanediol and 2-methyl- 1,4-butanediol was pumped out of the feed container into the reaction pot. A portion of the cyclized product was pumped back to the top of the Oldershaw column as reflux.
- Reflux ratio was controlled at about 0.3 by adjusting the reflux pump rate. The entire system was kept under a nitrogen atmosphere. The mixture of 1 ,4-butanediol and 2-methyl- 1 ,4-butanediol was fed to the cyclization unit for 103 hours.
- Product made during the last 27 hours of cyclization contained representative levels of impurities as compared to typical commercial plant cyclized product (i.e.. in the range of 150 to 200 ppm of each 1.3-dioxolane and
- This partially dried material was then passed through a 2 inch diameter glass column packed with 4A molecular sieves to reduce its water content to about 0.03 wt%.
- the dried product was then hydrogenated in a one-half inch diameter trickle bed reactor using Raney Ni 2800 as the catalyst.
- the reactor was operated at 90°C and 130-140 psi hydrogen pressure.
- the hold-up time was 7-10 minutes based on liquid flow rate.
- the hydrogenated product was then continuously fed to a 1 inch diameter Oldershaw column where most of the THF was removed overhead at a reflux ratio of 3/1 and a final product consisting of approximately 50 wt%
- a portion of the refined THF/3-methyl THF product was diluted to about 30 wt% 3-methyl THF with THF, and this solution was polymerized with fluorosulfonic acid catalyst for 4 hours at 35 °C (200 g THF/3-methyl THF to 23.1 g FSO3H). After quenching the catalyst with water, unreacted material was distilled off, the copolymer washed several times with water, then lime was added for neutralization. The remaining water was then distilled off and the copolymer dried under reduced pressure at 120-130 °C before it was filtered. The APHA color measurement of the filtered copolymer was 93.
- Dewatered, topped l,4-butanediol/2- methyl- 1 ,4-butanediol was pumped out of the feed container into the reaction pot. A portion of the cyclized product was pumped back to the top of the Oldershaw column as reflux. Reflux ratio was controlled at about 0.3 by adjusting the reflux pump rate. The entire system was kept under a nitrogen atmosphere. Dewatered, topped l ,4-butanediol/2-methyl- 1.4-butanediol was fed to the cyclization unit for about 50 hours.
- This partially dried material was then passed through a 2 inch diameter glass column packed with 4A molecular sieves to reduce its water content to about 0.03 wt%.
- Half of the dried product was then hydrogenated in a one-half inch diameter trickle bed reactor using Raney Ni 2800 as the catalyst.
- the reactor was operated at 90 °C and 130-140 psi hydrogen pressure.
- the hold-up time was 7-10 minutes based on liquid flow rate.
- the hydrogenated product was then continuously fed to a 1 inch diameter Oldershaw column where most of the THF was removed overhead at a reflux ratio of 3/1 and a final product consisting of approximately 50% 3-methyl THF in THF was refined overhead away from the remaining "high boilers".
- a portion of the refined THF/3-methyl THF (characterized as having no measurable 1,3-dioxolane and ⁇ 5 ppm 4-methyl- 1,3-dioxolane) product was diluted to about 30 wt% 3-methyl THF with THF, and this solution was polymerized with fluorosulfonic acid catalyst for 4 hours at 35 °C (200 g THF/3-methyl THF to 22.9 g FS0 3 H). After quenching the catalyst with water, unreacted material was distilled off, the copolymer washed several times with water, then lime was added for neutralization. The remaining water was then distilled off and the copolymer dried under reduced pressure at 120- 130 °C before it was filtered. The APHA color measurement of the filtered copolymer was 0.
- the finishing column tops associated with recovery of the topped 1.4-butanediol/2-methyl- 1.4-butanediol contained 2 to 7 wt% each ethylene and propylene glycol. No glycols or other low boilers were detected in the finishing column bottoms (i.e.. desalted, topped l,4-butanediol/2-methyl- 1 ,4-butanediol). Initially the cyclized THF/3-methyl THF product showed 2 to 3 ppm each of 1,3-dioxolane and 4-methyl- 1.3-dioxolane with 250 to 300 ppm 1,3 dioxepanes.
- THF/3-methyl THF from the campaign was collected and stored in two railcars.
- the first contained 51.5 wt % 3-methyl THF with 6 ppm 1,3-dioxolane and 16 ppm 4-methyl- 1,3-dioxolane.
- the second railcar contained 47.4 wt% 3-methyl THF with 12 ppm 1,3-dioxolane and 32 ppm 4-methyl- 1,3-dioxolane.
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Furan Compounds (AREA)
- Polyethers (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU41100/96A AU4110096A (en) | 1994-11-08 | 1995-11-01 | Process for the removal of color forming material from 1,4 butanediol and its application to the preparation of ptmeg |
DE69520072T DE69520072T2 (de) | 1994-11-08 | 1995-11-01 | Verfahren zur entfernung von fortbildenden stoffen aus 1,4-butandiol und dessen verwendung zur herstellung von ptmeg |
EP95939158A EP0790971B1 (en) | 1994-11-08 | 1995-11-01 | Process for the removal of color forming material from 1,4 butanediol and its application to the preparation of ptmeg |
JP51554596A JP3324759B2 (ja) | 1994-11-08 | 1995-11-01 | 1,4−ブタンジオールからの着色物質の除去方法およびptmeg製造へのその応用 |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US33635694A | 1994-11-08 | 1994-11-08 | |
US49595895A | 1995-06-28 | 1995-06-28 | |
US08/336,356 | 1995-06-28 | ||
US08/495,958 | 1995-06-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996014281A1 true WO1996014281A1 (en) | 1996-05-17 |
Family
ID=26990164
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1995/014849 WO1996014281A1 (en) | 1994-11-08 | 1995-11-01 | Process for the removal of color forming material from 1,4 butanediol and its application to the preparation of ptmeg |
Country Status (7)
Country | Link |
---|---|
US (1) | US5596074A (zh) |
EP (1) | EP0790971B1 (zh) |
JP (1) | JP3324759B2 (zh) |
CN (2) | CN1092625C (zh) |
AU (1) | AU4110096A (zh) |
DE (1) | DE69520072T2 (zh) |
WO (1) | WO1996014281A1 (zh) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1997026255A1 (de) * | 1996-01-16 | 1997-07-24 | Linde Aktiengesellschaft | Verfahren und vorrichtung zur herstellung von tetrahydrofuran |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10237954A1 (de) * | 2002-08-20 | 2004-03-04 | Basf Ag | Verfahren zur Herstellung von Tetrahydrofuran |
JP2011162780A (ja) * | 2010-01-15 | 2011-08-25 | Mitsubishi Chemicals Corp | ポリエーテルポリオールの製造方法 |
JP2013060429A (ja) * | 2011-08-23 | 2013-04-04 | Mitsubishi Chemicals Corp | 1,4−ブタンジオールの精製方法及びテトラヒドロフランの製造方法 |
WO2013086160A1 (en) * | 2011-12-08 | 2013-06-13 | Oakwood Foods, Llc (D/B/A Oakwood Technologies) | Continuous coolant purification process and device |
JP6241380B2 (ja) * | 2013-09-19 | 2017-12-06 | 三菱ケミカル株式会社 | 1,4−ブタンジオール、該1,4−ブタンジオールを用いたポリエステルの製造方法及び該1,4−ブタンジオールの貯蔵方法 |
CN115109247A (zh) * | 2022-08-02 | 2022-09-27 | 南京理工大学 | 一种含有甲基侧链的四氢呋喃-乙二醇共聚醚及其合成方法 |
CN115322363A (zh) * | 2022-08-02 | 2022-11-11 | 南京理工大学 | 一种1,4-丁二醇和聚乙二醇的交替共聚醚及其合成方法 |
CN117430485B (zh) * | 2023-10-18 | 2024-06-21 | 福建聚创新材料科技有限公司 | 基于负能耗分离残液中bdo的方法 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3852164A (en) | 1973-03-30 | 1974-12-03 | S Chow | Purification of 1,4-butanediol by vacuum distillation with side stream recovery |
US4257961A (en) | 1980-06-11 | 1981-03-24 | E. I. Du Pont De Nemours And Company | Purification of tetrahydrofuran |
US4383895A (en) | 1980-08-21 | 1983-05-17 | E. I. Du Pont De Nemours And Company | Purification of 1,4-butanediol |
US4419189A (en) | 1982-01-11 | 1983-12-06 | E. I. Du Pont De Nemours & Co. | Distillation of 1,4-butanediol |
US5209825A (en) | 1988-10-04 | 1993-05-11 | E. I. Du Pont De Nemours And Company | Preparation of purified concentrated BDO |
Family Cites Families (11)
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US2870097A (en) * | 1955-07-01 | 1959-01-20 | Du Pont | Process for the preparation of polymeric acetals |
DE2015672C3 (de) * | 1970-04-02 | 1979-08-16 | Woelm Pharma Gmbh & Co, 3440 Eschwege | Verfahren zum Herstellen von Platten und Folien für die Chromatographie, insbesondere für die Dünnschichtchromatographie, und Adsorbens zur Durchführung des Verfahrens |
JPS5293763A (en) * | 1976-02-04 | 1977-08-06 | Mitsubishi Chem Ind Ltd | Preparation of tetrahydrofuran |
DE3112065A1 (de) * | 1981-03-27 | 1982-10-07 | Basf Ag, 6700 Ludwigshafen | Verfahren zur herstellung von polytetramethylenether-glykol oder -glykoldiester mit niedriger farbzahl |
US4590312A (en) * | 1983-06-08 | 1986-05-20 | E. I. Du Pont De Nemours And Company | Process for preparing 2-alkyl-1,4-butanediols |
US4590285A (en) * | 1983-06-08 | 1986-05-20 | E. I. Du Pont De Nemours And Company | Process for preparing a mixture of tetrahydrofuran and 3-alkyl tetrahydrofuran and copolymers thereof |
US4940758A (en) * | 1987-12-29 | 1990-07-10 | Shell Oil Company | Polyalcohol |
DE3909485A1 (de) * | 1989-03-22 | 1990-09-27 | Basf Ag | Verfahren zur herstellung von butandiol-1,4 und tetrahydrofuran |
DE3935750A1 (de) * | 1989-10-27 | 1991-05-02 | Basf Ag | Verfahren zur herstellung von hochreinen polymerisaten des tetrahydrofurans |
DE4014923A1 (de) * | 1990-05-10 | 1991-11-14 | Basf Ag | Verfahren zur herstellung von urethan- oder urethan- und isocyanuratgruppen enthaltenden hartschaumstoffen nach dem polyisocyanat-polyadditionsverfahren und die hierfuer geeigneten polyoxyalkylen-polyole |
NZ239713A (en) * | 1990-09-11 | 1993-03-26 | Du Pont | Fluidised bed polymerisation of a cyclic compound by ring opening; compositions of ring-opened polymerisable compounds and initiators |
-
1995
- 1995-11-01 AU AU41100/96A patent/AU4110096A/en not_active Abandoned
- 1995-11-01 JP JP51554596A patent/JP3324759B2/ja not_active Expired - Lifetime
- 1995-11-01 DE DE69520072T patent/DE69520072T2/de not_active Expired - Lifetime
- 1995-11-01 EP EP95939158A patent/EP0790971B1/en not_active Expired - Lifetime
- 1995-11-01 WO PCT/US1995/014849 patent/WO1996014281A1/en active IP Right Grant
- 1995-11-01 CN CN95196103A patent/CN1092625C/zh not_active Expired - Lifetime
- 1995-12-22 US US08/577,943 patent/US5596074A/en not_active Expired - Lifetime
-
2000
- 2000-10-09 CN CN00133101A patent/CN1122065C/zh not_active Expired - Lifetime
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3852164A (en) | 1973-03-30 | 1974-12-03 | S Chow | Purification of 1,4-butanediol by vacuum distillation with side stream recovery |
US4257961A (en) | 1980-06-11 | 1981-03-24 | E. I. Du Pont De Nemours And Company | Purification of tetrahydrofuran |
US4383895A (en) | 1980-08-21 | 1983-05-17 | E. I. Du Pont De Nemours And Company | Purification of 1,4-butanediol |
US4419189A (en) | 1982-01-11 | 1983-12-06 | E. I. Du Pont De Nemours & Co. | Distillation of 1,4-butanediol |
US5209825A (en) | 1988-10-04 | 1993-05-11 | E. I. Du Pont De Nemours And Company | Preparation of purified concentrated BDO |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1997026255A1 (de) * | 1996-01-16 | 1997-07-24 | Linde Aktiengesellschaft | Verfahren und vorrichtung zur herstellung von tetrahydrofuran |
US6204399B1 (en) | 1996-01-16 | 2001-03-20 | Linde Aktiengesellschaft | Process and arrangement for producing tetrahydrofuran |
Also Published As
Publication number | Publication date |
---|---|
CN1092625C (zh) | 2002-10-16 |
US5596074A (en) | 1997-01-21 |
JPH10508638A (ja) | 1998-08-25 |
DE69520072D1 (de) | 2001-03-15 |
CN1304948A (zh) | 2001-07-25 |
AU4110096A (en) | 1996-05-31 |
EP0790971B1 (en) | 2001-02-07 |
EP0790971A1 (en) | 1997-08-27 |
CN1162952A (zh) | 1997-10-22 |
DE69520072T2 (de) | 2001-09-06 |
CN1122065C (zh) | 2003-09-24 |
JP3324759B2 (ja) | 2002-09-17 |
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